Starch has received much attention as a promising natural material both in biomedical fields and waste water treatment due to its unique biological and adsorptive properties. Recently, the modification of starch is rapidly developed along with its growing applications. This review focuses on the ways of chemical modification of starch including cross-linking, grafting, esterification, etherification, dual modification and so on, and presents the applications of the modified starch in fields like drug delivery, tissue engineering and heavy metal and dye removal.

Photovoltaic-thermal (PV/T) collectors have gained a lot of attention in recent years due to their substantial advantages as compared to ST or PV systems alone and even to other non-solar technologies. However, PV/Ts are still not as popular in industry or construction and they are not even known to major players implementing solar energy installations. In this article, a general presentation of PV/Ts and a review of their applications are given. First, different heat extraction media (e.g., air, water, bi-fluid, etc.) and hybrid design configurations of hybrid PV/T collectors are addressed. Next, the main applications of PV/T collectors are discussed in order to highlight their feasibility and usefulness and to raise awareness for adoption in the industry and buildings sector. Applications include desalination, air-conditioning, drying, trigeneration, etc. This paper should be considered as a reference form of PV/Ts to extract key points for future research and development as well as for other applications.

This paper deals with photovoltaic-thermal (PV/T) collectors that combine photovoltaic (PV) module and solar thermal (ST) modules to provide heat and electricity simultaneously. The use of a PV/T system not only enhances PV efficiency but also allows to use solar thermal energy for various heating applications. The performance evaluation of the PV/T collectors had been investigated both theoretically and experimentally for the past few years. In this work, we consider a new water-based PV/T configuration by incorporating a tedlar layer and parallel tubes and further investigate its modeling. The aim is to develop a non-linear dynamic model which gives a realistic and reasonable performance of the system. The fundamental equations are determined for the thermal part using a bond graph approach which is a generic and general tool to represent thermal transfers. Simulations are given to highlight the usefulness of the proposed design and its modeling, considering the influence of some external factors (e.g. wind action) and internal geometrical parameters (e.g. insulator thickness). The results indicate that the rise in wind speed can reduce thermal efficiency from 70% to approximately 40%. The results also show that with an increase in insulator thickness, there is a sudden change in outlet temperature but thicknesses of more than 0.14 m is not required as the energy losses become constant. The assessment of the electrical and thermal performance of a PV/T collector is taken into consideration for a sample weather condition of southern France. Further, our results are compared to existing experimental and numerical ones from the literature on alternative PV/Ts design to validate and demonstrate the viability and consistency of our model.

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This paper considers a bond graph approach to model a solar photovoltaic-thermal panel (PV/T) system as an alternative to the method used in [3]. Based on the obtained 1d model representing the dynamics of the PV/T, we identify transfer functions connecting the air output temperature to the air input flow for different operating points. Further, a PI-type controller is proposed and proven to guarantee good performance. All the techniques presented are illustrated through simulation results.

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In this paper, a multiple thermal model for a water-based photovoltaic-thermal (PV/T) collector is constructed by mathematical transformation, using the boundedness of non-linear terms. Simulations have been performed and the results indicate that the convex polytopic transformation can accurately represent the non-linear model. Further, a Linear Matrix Inequality (LMI) approach is used to design an observer for estimating the states of the system. The efficiency and performance of the proposed observer in estimating the states of the system are shown through simulation.